ANATOMY 2 | 3rd Q Flashcards
The nervous system has three specific functions:
sensory input
integration
motor output
sensory receptors present in skin & organs respond to external and internal stimuli by generating nerve impulses that travel to the brain and spinal cord.
sensory input
the brain and spinal cord sum up the data received from all over the body and send out nerve impulses
integration
The nerve impulses from the brain and spinal cord go to the effectors , which are muscles and glands. Muscle contractions and gland secretions are responses to stimuli received by sensory receptors.
motor output
Divisions of the nervous system
central nervous system (cns)
peripheral nervous system (pns)
Also called nerve cells, which transmit nerve impulses.
neurons
Which supports and nourishes neurons
neuroglia
3 parts of Neuron structure
cell body
dendrites
axon
it contains the nucleus as well as other organelles.
cell body
are the many short extentions that receive signals from sensory receptors or other neurons.
dendrites
is the portion of a neuron that conducts nerve impulses.
axon
3 types of neurons
motor neurons
sensory neurons
interneurons
take nerve impulses from the CNS to muscles or glands.
motor neurons
are multipolar because they have many dendrites and a single axon.
motor neurons
take nerve impulses from sensory receptors to the CNS.
sensory neurons
is gray because it contains cell bodies and short , nonmyelinated fibers.
gray matter
are also known as association neurons , occur entirely within the CNS.
interneurons
is white because it contains myelinated axons that run together in bundles called tracts.
white matter